Macroetching with coffee

[iamdaniel]

Was curious to see what the results would be like after seeing someone using coffee on damascus steel.
So this is heated using oxy/propane for a short time then dropped in some really strong coffee.
My 1st attempted was with cold steel and soaked over night. Heating deffinatly speeds up the process.

 

[dutch2u2]

Did you drink the coffee afterwards !!!

 

[pedrobedro]

Did you drink the coffee afterwards !!!

Waste not want not as the saying goes.

 

[dutch2u2]

I use a microwave to warm my cold coffee

 

[iamdaniel]

Sure why not, definatly got an irony aftertaste though.

 

[dobbslc]

Could start a new trend with the hipsters in Hoxton...

 

[iamdaniel]

Damn hipsters!

 

[dutch2u2]

How many sugars in the coffee.....

 

[fizzy]

I suspect coca cola or similar would work due to phosphoric acid.
For aluminium they say to use oven cleaner - it has sodium hydroxide in it!

 

[winchman]

Some people use coffee for developing film photos I was amased

 

[Johnnybravo]

Could start a new trend with the hipsters in Hoxton...

They suffer from a lead deficiency not an iron deficiency

 

[zx9]

Some people use coffee for developing film photos I was amased

Yes there are numerous film developer brews for Caffenol, less well known is using beer.
Caffenol recipes

 

[iamdaniel]

Well i seems to have got this down now. Polishing up the grades to 600grit.
Putting the sample in boiling water and leaving it for 5 mins, repeat for 2nd cup of water.
Then putting it in a half full cup with 3 scoops of coffee. Leave for 5 mins and then rinse.
Below is the result. The weld looked good on the outside but lack of root pen as can be seen.

 

[Munkul]

That's really interesting... I've always used phosphoric acid or stainless steel passivating chemical. It also needs a bit of heat to work. Those are lovely crisp etches, so the coffee works great, I may use that idea myself.

What sort of coffee? Instant or real ground coffee? Serious question...

 

[voipio]

I'd say there was penetration there, apart from one side of the root, but the filler composition may well be different to the metal being welded, resulting in different grain structure, plus some changes in the heat affected zone.

 

[iamdaniel]

That's really interesting... I've always used phosphoric acid or stainless steel passivating chemical. It also needs a bit of heat to work. Those are lovely crisp etches, so the coffee works great, I may use that idea myself.

What sort of coffee? Instant or real ground coffee? Serious question...

Instant Nescafe, I've got fresh ground here too, but i'm struggling to part with any for the project haha.

We ended up getting rid of the acid, the person that was doing this before me used to do it in the office staffs kitchen and there were a few complaints.

 

[Dr.Al]

That's really interesting... I've always used phosphoric acid or stainless steel passivating chemical. It also needs a bit of heat to work. Those are lovely crisp etches, so the coffee works great, I may use that idea myself.

What sort of coffee? Instant or real ground coffee? Serious question...

When I did a Damascus knife course at Oldfield Forge, they told me to do a coffee etch when I got it back home (it had already had a ferric chloride etch while I was there).

The instructions I was given were to buy "the cheapest, nastiest instant coffee you can find". The logic was that the posh instant coffees (if that isn't an oxymoron) were filtered to remove a lot of the stuff that did a good job of etching the steel (and probably your stomach!) whereas the cheap stuff still had it all still present.

 

[tom2207]

When I did a Damascus knife course at Oldfield Forge, they told me to do a coffee etch when I got it back home (it had already had a ferric chloride etch while I was there).

The instructions I was given were to buy "the cheapest, nastiest instant coffee you can find". The logic was that the posh instant coffees (if that isn't an oxymoron) were filtered to remove a lot of the stuff that did a good job of etching the steel (and probably your stomach!) whereas the cheap stuff still had it all still present.

no wonder it stains your teeth then ,,,,